Ventilator cover



M. WASSERMAN VENTILATOR COVER Filed May 19, 1952 Aug. 20, 1957 I 28. 32.a Z

v INVENTOR. l M ss r m an VENTILATOR COVER Max Wasserman, Brookline,Mass.

Application May 19, 1952, Serial No. 288,746

4 Claims. (Cl. 98-84)- The present invention relates to a ventilatorcover and more particularly to a stationary type ventilator such as maybe used in oflice buildings, apartment houses, hospitals, residences andthe like.

The cover of the ventilator of the general type with which thisinvention is concerned, is usually formed of a metal sheet and isretained by means of brackets to the air shaft or to some part of thestructure. The cover merely serves to prevent rain and moisture fromcoming through the ventilator screen into the air shaft.

In the present invention the ventilator is so constructed that itpermits the use of a plastic dome or cover and uses a plastic dome orcover as a ventilator cap. One of the chief advantages in such aconstruction is that the plastic dome may be transparent and thereforepermits some light to enter into the air shaft, thereby keeping theinterior of the air shaft fresh at all times because of the action ofthe sunlight. It also has a drying effect on the ventilator and inaddition to these advantages, if the Ventilator is straight or onlyslightly turned, one can see upwards through the ventilator andtherefore more readily determine where a ventilator block may be. Thesame applies in looking down the ventilator.

A further advantage of the present invention is that by the use of aplastic cap or dome it may be so installed that it can be blown oflwhenexcessive pressure occurs at the top of the ventilator. As an additionalfeature to permit this to happen, the dome may be attached in such amanner that an upward force beyond a certain pressure per square inchmay be suflicient to blow the dome off while pressure of the wind whichis not upwards and. which can only approach the dome from the top orsides will not affect the dome in any way.

In the present invention a number of modifications are shown by means ofwhich the dome can easily be secured to the ventilator to accomplish theabove purpose.

Without further describing the merits and advantages of the presentinvention, the invention will be described in the specification setforth below when taken in connection with the drawings showing anembodiment of the invention in which: Figure 1 shows a section partlybroken away through a ventilator of the round type in-- corporating thepresent invention and taken along section. line 1-1 of Figure 5. Figures2 and 3 show a modifica-- tion of details of Figure 1, Figure 4 shows'insectional. elevation a further modification of the present invention-Figure 5 is a top plan view with a fragmentary section,. and Figure 6 isa cross sectional view taken on line 6-6 of Figure 5.

In the arrangement indicated in Figure 1, 1 represents: an air shaftwhich extends upwards or it may extend in any other direction throughthe roof. The air shaft 1 has supported at its top end an enclosedcollar or suction band 2 which may be attached to the end of the airshaft by means of a supporting frame 3 of brackets which are riveted asindicated at 4, 5, 6 and 7 to the top of the air shaft. The brackets 3may be formed as continuatates atent tions of the sections 9 of theflange 8 with transverse mem-' bers 3d extending inwardly to the shaft 1and terminatingin downwardly extending ends 3b adjacent the air shaft 1and riveted to it as indicated. Additional reinforcing ele-- ments 3aand 3c extending respectively between the lower and upper ends of theshaft and the member 3d are also provided. The band 2 is provided withan inwardly ex tending, inclined flange 8, which has downwardly extending portions or sections 9 riveted or bolted as indicated by therivets 10 to the collar or band 2. The sections 9 may not form acontinuous flange section and may be just a group of downwardlyextending flange elements. Similarly the inclined flange 8 may notextend all around the band 2 but may be formed in separate sectionsalthough in the present invention there is a distinct advantage inhaving a complete flange extending continuously all around the inside ofthe band 2 as will presently be seen.

The inclined flange 8 supports the plastic cap or dome. 19 about itsperipheral margin or flange 19a which may be made of a thermo-plastictransparent material as for instance, Plexiglas or any other suitableplastic resin, whether thermo-plastic or thermo-setting including the:

acrylic resins, vinyl compounds and other such similar.

materials, which should be transparent. The dome or cap 19 may beattached to the flange 8 by means of a: plurality of loose rivets 11under which may be placed a washer 12 against the surface of the dome orcap. The rivet 11 which is of a split rivet type with twin shanks 13,passes through a hole 14 in the plastic dome larger than the shank ofthe rivet. The split prongs of the rivet are slightly turned over orbent outwards as indicated by the ends 15 on the bottom side of theinclined flange 8 which has a hole through which the shank of the rivetextends. This hole should be a fairly close fit for the shank of therivet unlike the loose fitting hole 14 in the Plexiglas dome.

A number of spaced rivets around the cap or dome may be used to securethe dome firmly to the inclined flange 8 which is lower down than thetop edge of the band 2 and therefore not subject to being raised bycross winds across the roof. However any pressure from internal buildingexplosions or the like coming up through the air shaft will tend toforce the dome 19 upward, which in turn would pull the rivets 13 with itclosing the the open ends 15 of the rivets together and thereby permitthe dome to be blown off the top of the shaft. If desired the dome mayhave an ear and a chain or an eyelet and a chain with the chain securedeither to the roof or to the band or in any other way so that while itwill be blown ofl of the top of the air shaft, it will not be lost andcan again be put in place after the diflieulties causing the blowing offhave been corrected.

The cap or dome is preformed as a single unit and can readily beinstalled in a very few minutes.

Figure 3 shows a modification of the structure shown in Figure 1 to theextent that in place of using rivets 11 through the plastic dome itself,a plurality of arms or clamping tabs 16 may be used to hold the plasticdome or cap 19 to the flange 8. In this case the tabs 16 may be held tothe flange by means of rivets 17 which may be the same type of rivetdescribed in connection with Figure 1, that is a rivet having splitprongs 18 which will be forced by pressure applied through the air shaftso as to permit the tabs 16 to be forced upwards opening the rivet. Infact in the case of the structure in Figure 3, even a lesser force isrequired because of the mechanical advantage on the tabs 16 in forcingthe pulling of the rivet 17. The tabs 16, as is indicated in Figure 3has an ofiset angle piece which may have any desired width correspondingto the curvature of the edge of the cap 19. There may be a number ofthese spaced around the circumference of the dome or cap or there may beonly a few each having more than one rivet through them. In fact themember 16 could be formed as a complete ring about the edge of the dome.This however is not necessary, particularly when the edge of the plasticdome which may be thermoplastic antitherefore inflammable is protectedby a non-inflammable coating 19 which covers and coats the entire edgeof the plastic cap or dome. It has been determined that the greatestfire hazard to a plastic dome is at a sharp edge or an exposed edgerather than a flat plane surface. The means set forth in Figure 3,therefore provides a great advantage in fire hazard protection forplastic domes where the edge is normally exposed. The edge of the domein Figure 1 and in other embodiments of the invention may also similarlybe coated as indicated in Figure 3.

In Figures 1 and 3 the flange 8 is shown as inclined. The flange may behorizontal as indicated by the structure shown in Figure 2. In this casea bracket 2!} having a horizontal arm or flange 2 is attached to theband or collar 22. The cap or cover 23 which is of the same material asset forth above may be attached to the flange as previously described bymeans of rivets 24 with split ends 25 so as to permit the dome to beblown oif when excessive pressure occurs in the air shaft.

In Figures 1 and 3 the flange 8 is shown as inclined, in which case theforce maintaining the dome on the air shaft is not squarely up and down.In Figure 2 however, the force is directly up and down parallel to theforces exerted by the air pressure in the shaft and therefore thestructure in Figure 2 would blow off more easily than the structure inFigure 1. However the rivets of varying widths and sizes can be chosento compensate for these variations and may also be selected so that thedome will blow off at the desired pressure.

In the structure shown in Figure 4, the dome 2-6 is supported by acurved flange 27 which has downwardly extending arms or supportingprongs 28 which may be riveted to a supporting structure 32 extendingupwards from the air shaft 1. The supporting structure 32 comprises aseries of upwardly extending extensions of the shaft 1, or may ifdesired be coextensive with it. A collar 29 fitting the outside contourof the cap or dome 26 may cover the periphery of the dome and be held tothe flange 28 by means of a series of rivets 30 of the split type, aspreviously described, spaced about the circumference of the ring 29. Theattachment of the dome 26 to the flange 27 will be below the top edge ofthe band 2 so as to protect the edge of the dome from action by windsblowing across the roof.

In each of the constructions described above, a screen top 31 is placedor rests on the top of the air shaft and is independent of the capstructure and its supporting means.

In the construction shown in Figures 1, 2 and 3, the flanges need notextend beyond the edge of the screen 31, so that after the dome has beenremoved the screen can easily be removed for cleaning or forreplacement.

Figure 2 shows such a structure, but in Figure I, it will be noted thatthe flanges or members 55 extend beyond the edge of the screen 31. Thisneed not extend so far inward as to cover the screen 31 so that it maynot be readily removed.

Having now described my invention, I claim:

1. In a ventilator structure having a shaft and a framecircumferentially spaced therearound, means securing said shaft to saidframe, a plurality of bracket supports each having two elements oneelement attached to said frame and the other element extending inwardlyabout the frame and externally of said shaft, a plastic transparent domecovering the shaft and having an outwardly extending peripheral flangefitting on said other elements and means extending over the peripheralflange of the dome, aligned openings formed in the last named means andsaid other element, rivets having a split shank portion extendingdownwardly through the aligned openings and having heads at their upperends larger than the openings, said split shank portions being spreadlaterally below the openings and extending just beyond the margins ofthe openings, whereby an excessive upward pressure applied against thedome causes the rivets to pull upwardly through the openings effectingthe last named means to release the dome.

2. In a ventilator structure having a shaft and a framecircumferentially spaced therearound, means securing said shaft to saidframe, a plurality of bracket supports each having two elements oneelement attached to said frame and the other element extending inwardlyabout the frame and externally of said shaft, a plastic transparent domecovering the shaft and having an outwardly extending peripheral flangefitting on said other elements, said first mentioned frame extendingabove the edge of said peripheral flange means extending over theperipheral flange of the dome, aligned openings formed in the last namedmeans and said other element, rivets having split shank portionsextending downwardly through the aligned openings and having heads attheir upper ends larger than the openings, said split shank portionsbeing spread laterally below the openings and extending just beyond themargins of the openings, whereby an excessive upward pressure appliedagainst the dome causes the rivets to pull upwardly through the openingseffecting the last named means to release the dome.

3. In a ventilator structure having a shaft and a framecircumferentially spaced therearound, means securing said shaft to saidframe, a plurality of bracket supports each having two elements oneelement attached to said frame and the other element extending in anupwardly inclined inward direction of said frame and terminatingexternally of said shaft, a plastic transparent dome extending over theshaft and having an outwardly and downwardly inclined peripheral flangefitting over said other elements in face to face relation therewith,means for clamping the peripheral flange to said other elements, saidmeans comprising tab elements having portions offset in differentparallel planes with one offset portion extending over said peripheralflange and the other offset portion in contact with said other elements,aligned openings formed in both the portion of the tab in contact withthe said other elements and the other elements, rivets having splitshank portions extending downwardly through the aligned openings andhaving heads at their upper ends larger than the openings, said splitshank portions being spread laterally below the openings and extendingjust beyond the margins of the openings, whereby an excessive upwardpres sure applied against the dome causes the rivets'to pull upwardlythrough the openings effecting the tabs to release the dome.

4. In a ventilator structure having a shaft and a framecircumferentially spaced thercaround, means securing said shaft to saidframe, a bracket support having-a branch attached to said frame and abranch extending inwardly of the frame and terminating externally of theshaft, a plastic transparent dome extending over and covering the shaftand having an outwardly extending flange resting upon said inwardlyextending branch, means coating the outwardly extending peripheralflange with a non-inflammable covering and securing means clamping saiddome at its flange to said bracket said securing means comprising tabelements having portions offset in different parallel planes, with oneoffset portion extending over the peripheral flange and the other offsetportion in contact with the inwardly extending branch, aligned openingsformed in said other oifset portion and the inwardly extending branch,rivets having split shank portions extending downwardly through thealigned openings and having heads at their upper ends larger than theopenings, said split shank portions being spread laterally below theopenings and extending just beyond the margins of the openings,

whereby an excessive upward pressure applied against the dome causes therivets to pull upwardly through he openings allowing the tab elements torelease the peripheral flange of the dome.

References Cited in the file of this patent UNITED STATES PATENTS 6Preuthun Aug. 6, 1901 Warden Mar. 5, 1907 Welker Aug. 31, 1909 ThomsonJan. 20, 1925 Greig Dec. 6, 1938 Brown et a1 June 11, 1946 Kofi May 25,1954

